Tech:Engine/K Series/Fuel Pump
The stock diaphragm-type mechanical fuel pump provides between 2.8 and 4.5 psi of fuel pressure to the carburettor. It is actuated via a sprung arm, which has its own lobe on the camshaft. There is also supposed to be a spacer between the block and the fuel pump. If you keep breaking pump arms and springs, this could be the reason. Otherwise, the only problem with them is that the spring wears out after prolonged (ie: 25 years) use.
If you have an uprated carb, this may need to change as per specs of the carb. Usually, better carbs get pretty fussy. For example a sidedraft will want between 2.5 and 3 psi, but will need a pump with alot of fuel flow (as they use lots of fuel), which means you'll need a pressure regulator, which will have a return line. However, Corollas don't have a return line into the tank, so just T the fuel return back into the line before the fuel pump.
If you fit an electronic pump, simply make a metal plate to go over the hole in the block where the pump was. To make it look nice, trace a fuel pump gasket to make your plate.
Fuel Miser make rubber diaphragm kits to rebuild stock pumps, they retail for about 90 bucks.
Fuel Miser also make a generic solid state electronic pump which is ideal for stock and performance carb applications, which flows 1.5L/min and supplies 2-3psi of pressure. It retails for about AU$129.
Article by Superjamie
You will find that there is Two different types of pumps for the 4K (as far as I know) The one on my KE55 has a different arm that sits on the cam compared to the KE70 I also have. Here is a pic:
One on the left is from a KE55 and one on right is a KE70
Back to K Series
Back to Main Page